The present invention relates to methods of improving physical properties of polyhemiaminal and polyhexahydrotriazine polymers and networks, and more specifically to preparing polyhemiaminals and polyhexahydrotriazines having thermoplastic components incorporated at the molecular level.
Polyhexhydrotriazines (PHT's) and polyhemiaminals (PHA's) are an emerging class of high strength engineering thermosetting polymers that have a unique combination of properties. They have high modulus, solvent resistance, and resistance to environmental stress cracking, but they can be easily recycled by decomposition to monomers in a strong acid.
These polymers are, however, brittle and have poor impact resistance. The have high tensile strength around 52 MPa with yield stress generally below 5%, which limits the applications available for such materials. Conventional methods of mitigating brittleness in polymers, for example polymers such as epoxy resins, has focused on including an elastomeric material in the polymer matrix, either chemically or by blending. Such methods reduce the strength of the material by lower its modulus.
There is a need for a material with the advantages of PHT's and PHA's with low brittleness and high impact resistance, and a method of making such materials.